Engine operated insecticide sprayer



Aug. 25, 1959 A. C. CRAGG ET AL ENGINE OPERATED INSECTICIDE SPRAYER Filed Aug. '7. 1957 v INVENTORS APT/f0? 5'. 619/266 .gf/VAZQ 4. SCHUZOT,

2,901,182 ENGINE OPERATED INSECTICIDE SPRAYER Arthur C. Cragg and Donald A. Schuldt, St. Paul, Minn., assignors to Donaldson Company, Inc., St. Paul, Minn, a corporation of Delaware Application August 7, 1957, Serial No. 676,867

4 Claims. (Cl. 239--129) Our invention relates generally to devices for spraying insecticides and the like to shrubbery and other insect infected areas, and more particularly to such devices which are adapted to be mounted on internal combustion engines to utilize the exhaust gases thereof as a vehicle for the insecticide.

An important object of our invention is: the provision of a sprayer which may be quickly and easily attached to the exhaust manifold of an internal combustion engine, and which not only operates to spray the material to be dispensed but also effectively muflles the sound of the explosions from the firing chamber of the engine.

Another object of our invention is the provision of an engine exhaust silencer and insecticide sprayer which may be applied to the exhaust manifold of an internal combustion engine without the necessity of modifying the engine or a vehicle on which the engine may be mounted, and without the use of special tools.

Another object of our invention is the provision of an attachment as set forth having a closed container for fluid to be sprayed, so that the spilling of the fluid is eliminated during operation of the sprayer, and of a novel arrangement of parts whereby gas is automatically introduced to the container to replace fluid drawn therefrom during the spraying operation.

Another object of our invention is the provision of a muifiier, on the shell of which is mounted a valve body having means for direct connection to a container for fluid to support the same in close coupled relation to the muffler and independently of the motor or the vehicle on which the motor is mounted.

Another object of our invention is the provision of an exhaust silencer and insecticide sprayer comprising, a mufiler, a valve and a fluid container constructed and arranged so that the container may be readily removed from the valve for filling and as readily replaced thereon, and so that the valve and container may be quickly and easily removed from the mufller when it is not desired to use the same, and as quickly and easily replaced.

Still another object of our invention is the provision of a novel exhaust silencer structure and sprayer combination including bathe means in the muffler and fluid discharge means from the container therefor so disposed with respect to said baflie and the mufiler inlet, that thorough mixing of the fluid with the engine exhaust gases is assured, weherby the insecticide is dispersed over the relatively wide area covered by the exhaust gas.

Another object of our invention is the provision of novel means whereby discharge of fluid from a supply container to the muffler is insured under varying back pressure conditions in the muffler.

The above and still further highly important objects and advantages of our invention, will become apparent from the following detailed specification, appended claims andattached drawings.

; [Referring to the drawings, which illustrate the invention, and in which like reference characters indicate like parts throughout the several views:

Fig. 1 is a view in end elevation of an engine exhaust silencer and insecticide sprayer made in accordance with our invention;

Fig. 2 is a view partly in side elevation and partly in section taken substantially on the line 22 of Fig. 1; and

Figure 3 is an enlarged view of a portion of the device shown in Figure 2.

In the preferred embodiment of the invention illustrated, the numeral 1 indicates, in its entirety, an elongated mufller comprising a generally cylindrical shell 2 to one end of which is secured a cap 3 having a plurality of discharge apertures 4 extending axially therethrough. At its opposite end, the shell 2 is tapered to provide a frusto-conical portion 5 which terminates in a reduced diameter sleeve 6 which receives an axial inlet in the nature of a nipple or pipe 7. Preferably, the pipe 7 is welded or otherwise rigidly secured to the sleeve 6 and extends axially inwardly slightly beyond the frusto-conical portion 5. At its outer end, the pipe 7 is threaded as indicated at 8, for reception in a threaded exhaust port usually found in exhaust manifolds of internal combustion engines of the type generally used with power lawn mowers and the like. Between the threaded portion 8 and the sleeve 6, the pipe 7 is provided with a nut-acting collar 9 for engagement with a Wrench or rpliers to facilitate mounting of the muflier on the exhaust manifold. In the interest of brevity, the showing and description of the engine with its exhaust manifold is omitted, neither the engine nor the exhaust manifold thereof in themselves comprising the instant invention. A transverse baffle element 10 is rigidly mounted in the interior of the shell 2 between the inner end of the inlet 7 and the end cap 3, and cooperates with the shell 2 to define inlet and outlet mufller chambers 11 and 12 respectively. The battle 10 further defines passages 13 for free movement of gases of combusiton between the inlet chamber 11 and the outlet chamber 12.

Welded or otherwise rigidly secured to the inner wall surface of the shell 2 and within the inlet chamber 11 above the inner end of the inlet 7 is a washer or pad 14, which with the overlying portion of the shell 2 is provided with a screw threaded opening 15 for reception of the screw threaded reduced bottom portion 16 of a valve body 17. At its upper end, the valve body 17 is provided with an upwardly opening internally threaded recess 18 in which is seated a sealing washer or gasket 19. An inverted generally cylindrical fluid container 20 is provided with a diametrically reduced neck or mouth 21 that is screw threaded into the recess 18, making sealing engagement with the gasket 19.

The valve body defines a gas passage 22 that extends vertically therethrough from the bottom of the reduced portion 16 to the recess 18 of the body 17. At its upper end portion, the gas passage 22 is counterbored to snugly receive the lower end of a gas tube 23 which extends upwardly through the recess 18 into the container 20, the upper end of the gas tube 23 terminating in closely spaced relation to the opposite closed end 24 of the container 20, well above the normal level of the liquid insecticide in the container 24 said insecticide being indicated at X. The liquid X in the container 20 may be of any one of a number of formulae suitable for insecticidal purposes, such as, for instance dichlorodiphenyl-trichloroethane (DDT) in a petroleum vehicle. The counterbored portion below the lower end of the gas tube 23 defines a seat 25 for a check ball 26, the lower end of said gas tube 23 being notched as indicated at 27, to permit gas under pressure to flow upwardly into the top of the container 20 when the check ball 26 is unseated by said gas under pressure.

Extending generally vertically through the valve body 17 is a fluid passage 28, the upper end of which opens into the recess 18 for communication with the interior of the container 20 through the mouth 21 thereof. The lower end of the fluid passage 28 communicates with the interior of. the chamber 11, the extended axis of the passage 28 intersecting the axis of the inlet 7 outwardly of the discharge end of said inlet. Intermediate its ends, the fluid passage 28 is formed to provide an offset portion 29 which defines a seat for a valve stem 30 that is screw threaded into the main body 17 for valving movements toward and away from the seat-forming offset portion 29 to control flow of the fluid X from the interior of the container 20 to the mufller chamber 11. At its outer end, the valve stem 30 is provided with a knurled knob 31 for easy manipulation of the valve stem 30.

With reference to Fig. 1, it will be seen that the main body 17 is provided at one side with a screw-threaded recess 32 for reception of a plug 33 that is adapted to be screw threaded into the opening when the main body 17 is removed therefrom under operating conditions wherein it is not desired to utilize the container and valve assembly. When the container and valve assembly are in use, the threaded recess 32 provides a convenient place of storage for the plug 33.

For the purpose of automatically draining off liquid insecticide which may accumulate in the bottom of the mufller 1 in the event that the operator shuts off the engiue but neglects to turn the valve stem 30 to its closed position, we provide a drain opening 34 in the bottom portion of the shell 2, see Fig. 2.

When the mufller 1 is attached to the exhaust manifold of an engine, and when the engine is in operation, the gases of combustion move into the mufller chamber 11 through the inlet 7 at a relatively high rate of speed and in a pulsating manner from the cylinder or cylinders of the engine. Opening of the fluid passage 28 by manipulation of the valve stem 30, permits the fluid X to flow into the path of movement of the exhaust gases from the inlet 7. As the fluid X enters the gas stream in the chamber 11, it becomes thoroughly mixed with the exhaust gases and atomized to a degree wherein it is carried outwardly through the discharge openings 4 in a finely divided mist or fog which thoroughly penetrates the shrubbery to be treated. As the liquid level in the container 20 is lowered, exhaust gas passes upwardly through the air passage 22, past the check ball and gas tube 23. During idle speeds of the engines, the mean back pressure within the mufiler 1 is sufiiciently low to permit flow of the liquid X to the chamber 11. At engine speeds above idling speed, back pressure in the mufller increases to a point wherein the normal head of liquid in the container 20 is not sufiicient to cause discharge of the liquid X to the chamber 11. Heretofore, in some instances, it has been necessary to add a small air pump to the container to overcome the increased back pressure. It is well known among those skilled in the art that gas pressure in the mufiier fluctuates With each pulsation of gas flow into the muffler. The check ball 26 permits entry of gas into the container 20 at the peak pressures of each pulsation and prevents return flow of gas to the mufiler through the passage 22, thus maintaining the interior of the container 20 under higher pressure than the mean pressure within the muffler 1 at all engine speeds, and insuring proper flow of the liquid X to the muffier chamber 11 at all time. When it is desired to replenish the supply of insecticide liquid X in the container 20, it is merely necessary to partially unscrew the muffler from the manifold, not shown, to a point wherein the container 20 underlies the mufiler 1, or to the extent of 180 circular degrees from its normal position. Thereafter, the container 20 is unscrewed from the recess 18 and refilled with insecticide. Obviously, after replacement of the container 20 on the valve body 17, the entire structure 4 is rotated until the container 20 again overlies the muflier as shown in Figs. 1 and 2.

If it is desired to use the mufller 1 without the valve body 17 and container 20, it is only necessary that the valve body 17 be unscrewed from the threaded opening 15 in the washer or pad 14, after which the opening 15 may be closed by removing the plug 33 from the recess 32 and screw threading the plug into the opening 15.

While we have shown a commercial embodiment of our novel engine exhaust silencer and insecticide sprayer, it will be understood that the same is capable of modification without departure from the spirit and scope of the invention as defined in the claims.

What we claim is:

1. In an engine exhaust silencer and insecticide sprayer, an elongated muffler shell having an inlet at one end adapted for connection to the exhaust manifold of an internal combustion engine and a discharge opening at its opposite end, a valve body having its lower end removably secured to one side of said muffler shell adjacent the inlet end thereof and an upwardly opening recess at its upper end for reception of the mouth of a fluid container, said valve body defining a gas passage and a fluid passage each extending generally vertically therethrough and communicating with the interior of said mufller shell and a fluid container applied to said body, said body further defining a valve seat in said fluid passage, a fluid control valve stem mounted in said body for valving movements toward and away from said seat, a gas tube extending upwardly from said body and defining an extension of said gas passage, said gas tube being adapted to be received in said container with the upper end of said tube disposed above the level of fiuid in said container, and check valve means permitting movement of exhaust gas through said gas passage and gas tube to the interior of said container but preventing return movement of said exhaust gas therethrough.

2. In an engine exhaust silencer and insecticide sprayer, an elongated mufiler shell having a reduced inlet adapted to be connected to the exhaust manifold of an internal combustion engine and extending longitudinally inwardly through one end wall of the shell, said shell having a discharge opening at its opposite end, a valve body removably mounted in a wall of said shell adjacent the inner end of said inlet and having an upwardly opening recess exterior of said shell for reception of the mouth of a fluid container, said valve body defining a gas passage and a fluid passage each extending generally vertically therethrough and communicating with the interior of said mufl ler shell and a fluid container applied to said body, said body further defining a valve seat in said fluid passage, a fluid control valve stem mounted in said body for valving movements toward and away from said seat, a gas tube extending upwardly from said body and defining an extension of said gas passage, said gas tube being adapted to be received in said container with the upper end of said tube disposed above the level of fluid in said container, and a check valve in said gas passage permitting movement of exhaust gas through said gas passage and gas tube to the interior of said container but preventing return movement of said exhaust gas therethrough.

3. The structure defined in claim 2 in which said rnuffler includes a transverse bafile element interposed between the discharge end of said inlet and the discharge opening at the opposite end of said casing, the extended axis of said fluid passage intersecting the axis of said inlet between the discharge end thereof and said baffle element.

4. In an engine exhaust silencer and insecticide sprayer, an elongated muffler shell having an inlet adapted to be connected to the exhaust manifold of an internal combustion engine and extending longitudinally inwardly through one end wall of the shell, said muffler shell having a discharge opening at its opposite end, a valve body removably mounted in a wall of said shell adjacent the inner end of said inlet and having an upwardly opening recess exterior of said shell, an inverted fluid container having a reduced mouth portion removably mounted in said recess, said valve body defining a gas passage and a fluid passage each extending generally vertically there through and communicating with the interior of said muffler shell and said fluid container, said body further defining a valve seat in said fluid passage, a fluid control valve stem mounted in said body for valving movements toward and away from said seat, a gas tube extending upwardly from the bottom of said recess and defining an extension of said gas passage, the upper end of said gas tube being disposed above the level of fluid in said container, and a check valve in said gas passage permitting movement of exhaust gas through said gas passage and gas tube to the interior of said container but preventing return movement of said exhaust gas therethrough.

References Cited in the file of this patent UNITED STATES PATENTS 1,769,266 Lusier July 1, 1930 2,591,585 Moore Apr. 1, 1952 2,606,068 Bonacor Aug. 5, 1952 2,611,992 Lay Sept. 30, 1952 2,665,943 Palm Jan. 12, 1954 2,685,146 Stevens Aug. 3, 1954 

